> On Feb 7, 2025, at 20:04, David Woodhouse <dw...@infradead.org> wrote:
>
> From: David Woodhouse <d...@amazon.co.uk>
>
> The vmclock device only has a reset method in order to plug its memory
> region into the system memory. It was originally done this way in order
> to defer the memory_region_add_subregion_overlap() from vmclock_realize(),
> but that doesn't seem to be necessary (any longer?).
>
> Still, allowing the platform code to do this is cleaner because it lets
> the address be specified by the platform, easing the port to Arm and
> other platforms in future. And the platform has to be involved anyway
> because of the need to include the device in the ACPI tables (or DT).
>
> So drop the reset method and provide a vmclock_mmio_map() function
> instead, called from pc_machine_done().
>
> Shift the ACPI table build into #ifdef CONFIG_ACPI_VMCLOCK too while
> we're at it, since it looks like that wouldn't have built when vmclock
> wasn't enabled.
>
> Signed-off-by: David Woodhouse <d...@amazon.co.uk>
Reviewed-by: Ani Sinha <anisi...@redhat.com <mailto:anisi...@redhat.com>>
> ---
> hw/acpi/vmclock.c | 18 ++++++------------
> hw/i386/acpi-build.c | 16 ++++++++++------
> hw/i386/pc.c | 10 ++++++++++
> include/hw/acpi/vmclock.h | 1 +
> 4 files changed, 27 insertions(+), 18 deletions(-)
>
> diff --git a/hw/acpi/vmclock.c b/hw/acpi/vmclock.c
> index 7387e5c9ca..36edfae0ed 100644
> --- a/hw/acpi/vmclock.c
> +++ b/hw/acpi/vmclock.c
> @@ -20,7 +20,6 @@
> #include "hw/qdev-properties.h"
> #include "hw/qdev-properties-system.h"
> #include "migration/vmstate.h"
> -#include "system/reset.h"
>
> #include "standard-headers/linux/vmclock-abi.h"
>
> @@ -107,15 +106,14 @@ static const VMStateDescription vmstate_vmclock = {
> },
> };
>
> -static void vmclock_handle_reset(void *opaque)
> +void vmclock_mmio_map(Object *dev, hwaddr addr)
> {
> - VmclockState *vms = VMCLOCK(opaque);
> + VmclockState *vms = VMCLOCK(dev);
>
> - if (!memory_region_is_mapped(&vms->clk_page)) {
> - memory_region_add_subregion_overlap(get_system_memory(),
> - vms->physaddr,
> - &vms->clk_page, 0);
> - }
> + vms->physaddr = addr;
> + memory_region_add_subregion_overlap(get_system_memory(),
> + vms->physaddr,
> + &vms->clk_page, 0);
> }
>
> static void vmclock_realize(DeviceState *dev, Error **errp)
> @@ -131,8 +129,6 @@ static void vmclock_realize(DeviceState *dev, Error
> **errp)
> return;
> }
>
> - vms->physaddr = VMCLOCK_ADDR;
> -
> e820_add_entry(vms->physaddr, VMCLOCK_SIZE, E820_RESERVED);
>
> memory_region_init_ram(&vms->clk_page, OBJECT(dev), "vmclock_page",
> @@ -149,8 +145,6 @@ static void vmclock_realize(DeviceState *dev, Error
> **errp)
> vms->clk->clock_status = VMCLOCK_STATUS_UNKNOWN;
> vms->clk->counter_id = VMCLOCK_COUNTER_INVALID;
>
> - qemu_register_reset(vmclock_handle_reset, vms);
> -
> vmclock_update_guest(vms);
> }
>
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 53b7306b43..9db7b1f94e 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -2446,7 +2446,7 @@ void acpi_build(AcpiBuildTables *tables, MachineState
> *machine)
> uint8_t *u;
> GArray *tables_blob = tables->table_data;
> AcpiSlicOem slic_oem = { .id = NULL, .table_id = NULL };
> - Object *vmgenid_dev, *vmclock_dev;
> + Object *vmgenid_dev;
> char *oem_id;
> char *oem_table_id;
>
> @@ -2519,12 +2519,16 @@ void acpi_build(AcpiBuildTables *tables, MachineState
> *machine)
> tables->vmgenid, tables->linker, x86ms->oem_id);
> }
>
> - vmclock_dev = find_vmclock_dev();
> - if (vmclock_dev) {
> - acpi_add_table(table_offsets, tables_blob);
> - vmclock_build_acpi(VMCLOCK(vmclock_dev), tables_blob, tables->linker,
> - x86ms->oem_id);
> +#ifdef CONFIG_ACPI_VMCLOCK
> + {
> + Object *vmclock_dev = find_vmclock_dev();
> + if (vmclock_dev) {
> + acpi_add_table(table_offsets, tables_blob);
> + vmclock_build_acpi(VMCLOCK(vmclock_dev), tables_blob,
> tables->linker,
> + x86ms->oem_id);
> + }
> }
> +#endif
>
> if (misc.has_hpet) {
> acpi_add_table(table_offsets, tables_blob);
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index b46975c8a4..776c2c8a37 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -60,6 +60,7 @@
> #include "hw/i386/kvm/xen_gnttab.h"
> #include "hw/i386/kvm/xen_xenstore.h"
> #include "hw/mem/memory-device.h"
> +#include "hw/acpi/vmclock.h"
> #include "e820_memory_layout.h"
> #include "trace.h"
> #include "sev.h"
> @@ -635,6 +636,15 @@ void pc_machine_done(Notifier *notifier, void *data)
> pci_bus_add_fw_cfg_extra_pci_roots(x86ms->fw_cfg, pcms->pcibus,
> &error_abort);
>
> +#ifdef CONFIG_ACPI_VMCLOCK
> + {
> + Object *vmclock = find_vmclock_dev();
> + if (vmclock) {
> + vmclock_mmio_map(vmclock, VMCLOCK_ADDR);
> + }
> + }
> +#endif
> +
> acpi_setup();
> if (x86ms->fw_cfg) {
> fw_cfg_build_smbios(pcms, x86ms->fw_cfg,
> pcms->smbios_entry_point_type);
> diff --git a/include/hw/acpi/vmclock.h b/include/hw/acpi/vmclock.h
> index 5605605812..97f8a30c0e 100644
> --- a/include/hw/acpi/vmclock.h
> +++ b/include/hw/acpi/vmclock.h
> @@ -30,5 +30,6 @@ static inline Object *find_vmclock_dev(void)
>
> void vmclock_build_acpi(VmclockState *vms, GArray *table_data,
> BIOSLinker *linker, const char *oem_id);
> +void vmclock_mmio_map(Object *dev, hwaddr addr);
>
> #endif
> --
> 2.48.1
>
>
